Go to file explorer and paste this address: C:\Program Files (x86)\Steam\steamapps\workshop\content\108600\2686972114\mods\DylanSensibleLoot\media\lua\server\Items now you can see there's a file called DylanSensibleDistributions.lua click on it then there will be a line of codes now find your preferred item you'll see there is a number below it, that is the chance of the zombie dropping that loot don't add % to the numbers or else it wont work now if you change the number to 100 then it will always drop that loot change it to any number you want and your done. Note that i don't fully know the codes of project zomboid so if you are a dev you can correct me.